The problem with this theory is that before a fighter gets a title shot a clause is added to their contract that essentially states that as long as the fighter is the champion the UFC reserves the right to match any offer from any other company when renewing the contract. This way a champion can only leave if the UFC refuses to pay him equal to a competitor.
He was not sent to the UFC it isnt like Pride didnt want him... Pride and the UFC probably made an agreement to have a battle of the 2 orgs as soon as Cro Crop wins the title, but it isnt like Pride fixed everything.